In manufacturing processes for a semiconductor device such as a large-scale integrated circuit (LSI), various cleaning processes are performed for the purpose of removing organic materials and the like on a semiconductor substrate. The cleaning processes typically include the steps of dipping a semiconductor substrate into a chemical solution, washing the semiconductor substrate with deionized water, and then drying the semiconductor substrate.
In the drying step, a drying rate is accelerated by taking out the semiconductor substrate to an alcohol atmosphere and consequently replacing moisture on a surface of the substrate with alcohol.
The above-mentioned drying step is described in detail in Japanese Patent Application Laid-open Publication No. Hei 11-354485, for example.
According to Japanese Laid-open Patent Publication No. 11-354485, occurrence of dew condensation on a surface of a substrate is prevented by heating, in the drying step, the substrate to a higher temperature than the higher one of a water dew point and an alcohol dew point, so that attachment of particles to the substrate attributable to the dew condensation is prevented.
In addition, the techniques related to the present embodiments are also disclosed in Japanese Laid-open Patent Publication No. 64-69015, Japanese Laid-open Patent Publication No. 2005-166958 and Japanese Laid-open Patent Publication No. 2003-273059.